The Short Message Service (SMS) is a messaging mechanism that can deliver messages of 140 octets/bytes between subscribers, or to/from an application, service, or other component in a network from/to a subscriber. SMS exists currently in GSM (Global System for Mobile communications) and UMTS (Universal Mobile Telephony System) and will likely be part of deployments in Third Generation Partnership Project (3GPP) LTE (Long Term Evolution) systems. The message payload commonly contains plain text, but there are provisions for other types of data, such as pictures, graphics, ring tones, etc. SMS is defined in 3GPP Technical Specification (TS) 23.040, and some elements (particularly the transport) are defined in 3GPP TS 29.002.